Electric-welding transformer



A. F. RlETZEL.

ELECTRIC WELDING TRANSFORMER.

APPLICATION FILED OCT. 3. I9I8 Patenmd May 20, 1919.

VENTOR 01/ 7-7 fi jezf 6/ 11770 NEYS' UNITED STATES PATENT OFFICE.

ADOLPH F. RIETZEL, 0F CHARLESTOWN, RHODE ISLAND, ASSIGNOR TO THOMSON ELECTRIC WELDING COMPANY, OF LYNN, MASSACHUSETTS, .A CORPORATION OF MASSACHUSETTS.

ELECTRIC-WELDING TRANSFORMER.

' Specification of Letters Patent.

Patented May 20, 1919.

To all whom it may concern:

Be it known that I, ADoLrH F. Rmrznn, a citizen of the United States. and a resident of Charlestown, in the county of \Vashington and State of Rhode Island, have invented certain new and useful Improvements in Electric-Welding Transformers, of which the following is a specification.

My present invention relates to the con struction of that class of electric metal working apparatus in which the work platens or holders or'work-engaging electrodes or j aws derive the heating current from the second ary of a transformer.

The object of the invention is to permit free movement of the work platens or jaws with relation to one another and at the same time maintain good electrical connection with the secondary or other source of current. Further objects are to secure simplicity of construction and high electrical efiiciency.

The invention consists in the improved electric metal working apparatus, particularly as regards the transformer construction and the means for conducting the current from the secondary thereof to the work jaws, as hereinafter more particularly described and then specified in the claims.

In the accompanying drawings:

Figure 1 is a general front elevation of a transformer secondary, conductors and work-platens constructed in accordance with this invention.

Fig. 2 is a fragmentary view showing a modification in the manner of connecting the secondary conductors to the platens.

Referring to the drawings, 1 indicates the transformer secondary which in the present case is a single turn of cast copper having repositories for the primary coils as is usual and well known in the art. The trans-- former, also as is usual, is provided with an iron core.-

' 2, 2 indicate the platens upon which the workholders or work-engaging electrodes are mounted. The platens as is usual in the art move toward each other by any suitable devices to apply the upsetting pressure to the work after the heating current has raised the temperature to the requisite extent. all as well understood in the art and needing no detailed description herein.

At each end of the turn of the secondary 1 a transformer groove or socket 3 is formed.

at, a indicate flexible conductors connecting each 'end of the secondary turn with one of the platens 2, 2. The conductors are by preference composed of thin laminated copper strips bundled together at the ends. The lower ends of the conductors are each provided with a fitting 5 disposed in the socket 3 in such manner that the fitting is free .to swivel or turn therein, thereby forming a hinged joint.

The upper end of each conductor may be secured to its platen in any desired manner. As shown in Fig. 1 the laminated strips are bundled together and rigidly secured to the platen whereas in Fig. the connection with the platen is made in the same manner as the joint at the lower end.

The hinged joint between the secondary turn and the conductor resembles an elongated ball and socket joint except that it is only necessary for the swiveling movement to take place in one plane to wit, the plane of movement of the platens 2, 2'.

The conductor leads at, 4 are made of such length that when secured to the secondary and to the platen they will become bowed or distorted, the laminations preferably dividing and bowing outwardly in opposite directions as shown in Fig. 1. In this way the leads act as a spring to exert a down ward pressure on the fitting 5 in the socket 3 thus causing a good electrical contact to be maintained. iVhen the hinge connection is employed at the upper end of the leads, the bowing also causing an upward pressure, a good electrical contact is maintained at that joint.

By providing the joints at the extreme ends of the secondary turns, the full eii'ect of the turn is obtained, thereby securing the highest efficiency.

In the drawing Fig. l, the full lines show the parts in the mean position of the platen, that is, when it has been moved about half of its travel. As it moves to either side of this position, the bowing of the conductor leads somewhat varies but the leads are still under sufficient tension to exert the necessary pressure at the hinge joints. The other positions taken by the leads are indicated in dotted lines,

It will be understood that the invention is not limited to use in any particular type of electric metal working apparatus except as may be specified in the appended claims.

Vhat I claim as my invention is 1. In an electric welding transformer, a solid secondary and a flexible conductor hinged to said secondary, said conductor being under tension to maintain a good electrical contact at the hinged joint.

2- In an electric welding transformer, a solid secondary and a flexible conductor hinged in a socket formed in said secondary, parts of said conductor being bowed with respect to other parts to maintain good electrical contact in said socket.

3. In an electric welding transformcr,-a secondary turn of solid metal having asocket at the end of the secondary turn and a flexible conductor the end of which seats and swivels in said socket, said conductor being under tension to exert presure between the conductor end and the socket.

4. In an electric welding transformer, a

' secondary turn of cast copper having a socket formed at the end of the secondary turn, a flexible conductor of laminated c0pper strips held under tension and a ballshaped head to which said copper strips are transformer secondary turn of solid metal provided with asocket at the end of the turn, a flexible conductor 'of laminated the combination with the work platens, of a v V strips connecting the secondary turn and the platens and a ball-shaped head to which the flexible conductor is secured seated in said socket, said laminated strips being bowed to apply pressure in the ball and socket joint, as and for the purpose described.

Signed at Charlestown, in the county of 'ashington and State of Rhode Island this 28 day of September All). 1918.

ADOLPH F. RIETZELL \Vitnesses Isaac Wxnsox, Rosa H. RIETZEL. 

